Senile dementia has become a serious problem both medically and socially with the arrival of a rapidly aging society in recent years. Thus, effective anti-dementia drugs have been strongly demanded. Although a great deal of research has been conducted on Alzheimer's disease (AD), the cause of the disease still remains to be elucidated. Aricept, the only therapeutic drug approved in Japan to treat Alzheimer's disease, is a drug having an inhibitory effect on acetylcholine esterase based on the cholinergic hypothesis. This drug is very useful as symptomatic treatment and however, does not serve as a drug for disease-modifying therapy.
Curcumin, a substance contained in turmeric, etc., has recently been reported to have a suppressive effect on Aβ aggregation and a degradative effect on Aβ aggregates (Non-Patent Document 1) and has therefore been expected as a novel therapeutic drug for Alzheimer's disease. Non-Patent Document 1: Yang. F, et al. J. Biol. Chem. 2005 Feb. 18; 280 (7) 5892-901